Drilling platform



Sept. 26, 1967 A. M. SMULDERS 3,343,372

. DRILLING PLATFORM FiiedMay 17. 1965 2 Sheets-Sheet 1 INVENTOR Y m Ja a/W ATTORNEY-S Sept. 26, 1967 A, H. M. SMULDERS 3,343,372

DRI LLING PLATFORM Filed May 17. 1965 v v 2 Shets-Sheet 2 IN VE N TOR. Ava usr A ia/pew Mme/A J/wuwaes W Y-JM,

United States Patent ABSTRACT OF THE DISCLOSURE A drilling platform of the type in which the platform and columns are vertically adjustable relative to each other, has five columns disposed in the corners of a regular pentagon, for increased safety against sagging.

The present invention relates to drilling platforms and the like, more particularly of the type in which a buoyant platform is provided with a number of columns movable vertically relative to the platform and adapted to be fixed in vertically adjusted positions.

Drilling platforms of this type have been devised in the past. In one form, such a drilling platform is provided with three columns or legs, by means of which the drilling platform can stand on the oceanfloor. It is also known to provide drilling platforms with four columns or legs mounted at the corners of a rectangle. Also, it is known to provide such platforms with six or eight columns, arranged in groups of three or four along the sides of a rectangle.

However, drilling platforms as heretofore conceived have all suffered from certain disadvantages. In the first place, a platform with three columns presents difliculties when the soil underneath one column washes away, as the drilling platform will then lean over and may even topple and be lost. Also, in the case of a drilling platform having three columns, the load on one column cannot be increased as desired unless the column in question is ballasted; and this ballasting is a complicated operation. This is true because the load imposed on any one column by a platform supported by three columns tends automatically to be equally distributed among the three.

Similarly, a drilling platform having four columns is undesirable. In theory, the weight which is borne by two diagonally opposite columns can be increased by decreasing the load on the other two diagonally opposite columns. In fact, however, the platform will thereupon assume an unstable position. Moreover, such a distribution is not even theoretrically possible unless the center of gravity of the platform is in the center of the platform; and this is seldom, if ever, the case. Moreover, when the soil underneath one of the columns of a platform with four columns is washed away, an unstable equilibrium may also be produced if the load is largely supported by the column from beneath which the soil has been washed away.

Similarly, drilling platforms with six or eight columns are characterized by certain disadvantages. Specifically, when a column in one of the corners loses its subjacent support, then certain conditions of wind loading or wave loading can cause the next column, on the same side as the unsupported column, to bear much more than its intended load. Thus, when wind or wave load is applied perpendicular to the line that extends diagonally between the two corners of the rectangle which are nearest to the vertex where the soil has been washed away, then the next column in the line is quite near that diagonal line and bears a very high load.

Accordingly, it is an object of the present invention to provide a drilling platform or the like which does not sulfer the above disadvantages when the soil washes out from beneath one of its columns.

It is also an object of the present invention to provide a drilling platform or the like as to which the load borne by one or more of the columns can be readily adjusted.

These and other objects and advantages of the present invention will become apparent from a consideration of the following description, taken in connection with the accompanying drawings, in which:

'FIGURE 1 is a somewhat diagrammatic plan view of a drilling platform according to the present invention; and

FIGURE 2 is a side elevational view of a drilling platform according to the present invention.

Briefly, the present invention comprises the discovery that the above objects can be achieved by providing a drilling platform having five columns or legs, which are disposed in the corners of a substantially equilateral pentagon. In a preferred form, the drilling platform itself is also pentagonal and substantially congruent with the pentagon whose vertices are marked by the columns or legs.

Referring now to the drawings in greater detail, there is shown a drilling platform comprised of a platform 1 which is in the form of a pontoon having positive buoyancy when the entire assembly is supported on the water, so that the drilling platform of the present invention may be floated from place to place as desired when its columns or legs are suitably raised. Platform 1 is in the form of a substantially equilateral pentagon as viewed in plan.

In each of the five corners of platform 1, there is provided an opening through each of which one of the vertical columns or legs 2, 3, 4, 5 and 6 extends. When platform 1 is horizontal, each of legs 2, 3, 4, 5 and 6 is vertical.

A framework 7 is mounted on the upper side of platform 1 adjacent each opening through which one of the columns extends. Each frame 7 provides a vertical guideway for the vertical movement of the associated column. Each frame 7 also carries means 8 for moving the associated column vertically relative to platform 1, and means 9 for selectively fixing the vertically adjusted position of the associated column relative to platform 1. These means comprise, in one embodiment, conventional teeth cooperating with locking bars, and jacks for the actuation of the moving parts, as shown in a number of earlier patents, among them my US. Patent No. 3,056,585, Oct. 2, 1962.

It will also be noted from FIG. 1, as indicated above, that the columns are disposed at the apices of an equilateral pentagon, and that that pentagon is substantially congruent with and disposed inside the pentagon defined by the contour of platform 1 in a horizontal plane.

The above construction has the advantages that when one column loses its subjacent support, and even when two columns which are not contiguous have lost their support, platform 1 will still remain standing on three columns, which will of necessity give three-point support. It is also possible, by raising one or more columns, to vary the load on the remaining columns. It will furtherbe noted that the loss of support by any single column, or by any pair of noncontiguous columns, cannot give rise to the imposition of undue loads on any of the remaining columns, as the diagonals between the remaining supported columns do not pass undesirably close to any supported column.

In view of the foregoing disclosure, it will be seen that all ofthe initially recited objects of the present invention have been achieved.

Although the present invention has been described and illustrated in connection with a preferred embodiment, it is to be understood that modifications and variations may be resorted to without departing from the spirit of the invention, as those skilled in this art will readily understand. Such modifications and variations are considered to be within the purview and scope of the present invention as defined by the appended claims.

Having described my invention, I claim:

1. A drilling platform or the like, comprising a buoyant platform, five vertical supporting columns disposed in the corners of a substantially equilateral pentagon, and means mounting the columns for vertical sliding movement relative to the platform.

2. A drilling platform as claimed in claim 1, the platform being in the form of a pentagon with the columns disposed in the corners of the pentagon.

for independently selectively fixing any of said columns in any of a plurality of vertically adjusted positions relative to the platform.

References Cited UNITED STATES PATENTS 2,906,100 9/1959 De Long et al 61--46.5 2,959,016 11/1960 Parks 61-465 3,171,259 3/1965 Roussel 6146.5 3,195,313 7/1965 Swatek 6146.5 3,246,476 4/1966 Wolfi 61-465 DAVID J. WILLIAMOWSKY, Primary Examiner.

3. A drilling platform as claimed in claim 1, and means 15 JACOB SHAPIRO Assistant Examiner- 

1. A DRILLING PLATFORM OR THE LIKE, COMPRISING A BUOYANT PLATFORM, FIVE VERTICAL SUPPORTING COLUMNS DISPOSED IN THE CORNERS OF A SUBSTANTIALLY EQUILATERAL PENTAGON, AND MEANS MOUNTING THE COLUMNS FOR VERTICAL SLIDING MOVEMENT RELATIVE TO THE PLATFORM 